The private farmers who till more than 75 percent of Poland's land did not receive enough seed, fertilizers, pesticides, or tools. They still managed to make a significant contribution to this food-short nation's larders. But not nearly as much as they might have done.

''It wes a perfect growing season and there's not a chance in 100 it will repeat itself again so soon as this year,'' the expert said. ''The government has got to find another answer.''

Five years of general agricultural decline, mainly because of neglect of private farmers' pleas for machinery and inputs, underlie the crisis that broke in mid-1980.

Probably only the military-type operation controlling distribution to ensure the basic ration of meat and other necessities has gotten Poland through this harsh winter without greater hazards. Had popular unrest over food shortages increasedit could have proved more dangerous to internal stability than political agitation.

So agriculture is getting official attention in a way it rarely has before. The government seems to be acknowledging that is the only way to win the support of private farmers in the vital battle for food.

In fact, it appears that agriculture is the one area where the promised continuation of the process of ''renewal'' is sure to go forward. The Polish parliament is soon to begin considering two bills that assure private farmers of legal title to their land and promise better state-funded social conditions in the countryside and more independence for farmers.

Three million prvate holdings spread over three-quarters of the arable area of Poland. Thase plots range from scarcely an acre (half a hectare) up to 125 acres, the maximum permitted by law.

A million are less than 12 acres. Nearly 1 million plots are worked by people at or past retirement age. Many owners have scattered parcels of land; almost all lack many of the elementary means of production.

For a decade, consumer items like cars - from the heavily invested Polish Fiat license - had priority over agriculture. And state farms got twice as much of the available production and technical means per acre as the private sector.

Private peasants pleaded in vain for ''simple farming tools'' and basic inputs. Rakes, spades, hammers, axes, scythes, and chains were no more forthcoming than was a tractor suited to small-scale farming.

Warsaw's Ursus tractor plant is still building a foundry started six years ago. Spread over 240,000 square meters of factory floor, the plant is based on British tractor and engine patents and has the biggest potential in Europe. But last year's output was 12 percent below 1980's. At present there reportedly are 50,000 units waiting for tires and oil filters.

Where modern agricultures use more than 4.5 pounds of pesticides per acre, Poland's gets less than half a pound. This alone cut the country's harvest by 15 to 20 percent last year.

This spring Polish farms will get even less fertilizer than last year, and only half as much seed.

But the private farmers were promised a new deal last year. And some farm reforms are moving forward, even though their union, Rural Solidarity, remains suspended.

This year the private sector is promised fully 60 percent of all resources available for farming. Agriculture Minister Jerzy Wojtecki says that ''increasing and stabilizing food production can only be possible if the countryside can purchase more fertilizer, pesticides, machines, and construction materials, and if we can enlarge land improvement and a broad area of services.''

Already, according to the Agriculture Ministry, more than 70 percent of machines are ready for use this year and more spare parts are available.

Production of equipment is being beefed up. Last year 30 factories switched to making the machines needed by small farms; 50 more will this year. ''More milk coolers. More potato diggers, disk harrows, binders, mowers, motorized fertilizer spreaders and . . . and . . . .''

Poland's peasant farmers have heard much of this before. So they are waiting to see how well the regime delivers.

If it does follow through, the result could be a ''revolution,'' not just a reform of Polish agriculture.

For even the handling of the state farms is changing. They have been told, in short, that they are ''on their own'' and must operate on a profit basis.At the start of this year, they were ordered to shift to profit and loss accounting. The massive subsidies that shored many of them up for 25 spendthrift years have been canceled. If a state farm continues to lose money, the manager will be replaced.

Under the reorganization, directives from the center -- specifying, for example, what a farm should grow -- are precluded, as are subsidies. This could compel the state farms to switch from cattle raising to grain production on thousands of acres thus far left idle.Despite the decline of recent years private farmers produce most of Poland's meat and dairy products. ''Give them incentives and the tools of production, and they can and will raise much more,'' the expert said. ''And in the four years needed to raise beef, the state farms can deliver four grain crops.''

It has taken martial law and resulting Western sanctions to bring home the fallacy of an agricultural policy that left the country dependent on imports for its bread and animal feed. It accrued huge foreign debts and drained away hard currency badly needed elsewhere in the economy.

The pending about-face in agriculture could lead to private farms much larger than present ''maximum'' holdings, for the legislation assures not only security of tenure to the private farmer but also his legal right to pass his land on to his son or to sell it to another farmer.

Although collectivization was never as ruthlessly applied in Poland as elsewhere in Eastern Europe, it has meant continuing official discrimination in favor of the state farms. Private farmers have often suspected that government talk of ''socialization of the village'' was just a euphemism for collectivization.

Nevertheless, the government has handled Rural Solidarity much more gently than Lech Walesa's union. There have been few attacks on the farmers' union. Those that have occurred had none of the vehemence of the campaign against workers' Solidarity.

If Rural Solidarity was influenced by any outside political force, it was the Roman Catholic Church - and not the radicals advising Solidarity. The Communist leadership has no wish to fight either with the church or the peasants.

Traditional peasant hunger for land has hindered modernization and rationalization of Polish farming. It has meant small - often miniscule - plots, and primitive husbandry. But the profile of the countryside is changing. Although drift of young people to towns and industry has slowed, fewer sons are available to take over family farms.

This can only lead to more sales of land among farmers themselves. More private farms are likely to reach the maximum 125 acres.

In mountainous and marginal regions the limit is already 250 acres. The authorities apparently envisage this for the farming commenity generally. Some hint at eventual leveling-off in nonstate farming at 400,000 to 500,000 substantial holdings.